安徽省凤阳小岗村党支部书记沈浩带领干部群众走向致富路。后沈浩因积劳成疾倒在工作岗位上，国家发出了学习宣传沈浩先进事迹的号召。向沈浩同志学习，我们应该（   ）

①发扬艰苦创业精神

②不言代价与回报地履行责任

③增强社会责任感和使命感

④全身心投入到社会公益活动中

句型转换

（1）Her father can play basketball and table tennis. (改为否定句)

Her father ____  ____ basketball ____ table tennis.

（2）Lucy can dance well. Can you dance well? (改为同义句)

Lucy can dance well. ____  ____you?

（3） Don't be worried about me. (改为同义句)

Don't ____  ____ me.

（4）Mike can play basketball well. (改为一般疑问句并作肯定回答)

—____ Mike ____ basketball well?

—____, he____.

（5）I want to join the Dance Club. (改为同义句)

I ____  ____  ____ join the Dance Club.

在化学反应前后，可能发生改变的是（      ）